Several methods have been developed for repairing corroded pipes (such as those laid on the ocean floor) by inserting new pipes into existing structures. The following published unexamined Japanese patent applications relate to pipe repair: JP No. Showa 63 (1988)-23578, JP No. Heisei 1 (1989)-54595, JP No. Heisei 3 (1991)-4027, and JP No. Heisei 3 (1991)-30757.
Conventional methods of reconstructing corroded pipes have several limitations. Efficient insertion of a new pipe into a pre-existing pipe requires that the length of new pipe being inserted be longer than the old pipe. However, there are limits regarding the distance to which a jack can be extended in order to advance a new pipe into a pre-existing pipe. In addition, during insertion the new pipe can lurch forward if the frictional resistance between the inner surface of the old pipe and the outer surface of the new pipe is broken. Thus there is a need for an improved method of reconstructing pipes.